1. Field of the Invention
This invention relates to a picture recording method and apparatus and a picture reproducing method and apparatus. The present invention may be applied with advantage to, for example, a digital camera device for digitizing a picture and for recording the digitized picture.
2. Related Art
Recently, as personal computers are coming into widespread use, digital camera devices, configured for digitizing and recording pictures, are stirring up notice as picture recording devices. As the digital camera devices, there are known such devices in which a pre-set number of object are digitized and recorded in a pre-set recording medium such as a memory card as still-picture data so that the still pictures can be subsequently outputted to a monitor of the personal computer. The digital camera device usually has the function as a picture reproducing device of displaying a picture recorded on a pre-set recording medium from a picture display unit, such as a LCD panel, provided on the back side of the device. In addition, the digital camera device occasionally has the function of editing picture data such as erasing a recorded picture corresponding to an unneeded picture or an unsatisfactory picture.
Meanwhile, when recording plural still pictures on a pre-set recording medium, samples of recorded pictures are desirably recorded on the recording medium for convenience in picture display during reproduction or in picture editing operations. This sample of pictures is usually termed a thumbnail and frequently recorded as thumbnail picture data corresponding to decimated data of the recorded picture. In reproducing a picture, only the thumbnail picture data are read out from the recording medium and presented to the picture display unit in the form of contracted pictures. The user then specifies one of the displayed plural thumbnail pictures, whereby picture data corresponding to the thumbnail pictures are read out from the recording medium so as to be displayed on the picture display unit.
Also, in erasing picture data by way of the above-mentioned editing operation, it is customary practice to read out only thumb-nail picture data from the recording medium to display the data corresponding to a plurality of contracted pictures on the picture display unit. In this case, the user specifies an unneeded one of the displayed plural thumbnail pictures to erase the picture data corresponding to the thumbnail pictures from the recording medium.
Since the thumbnail picture is displayed prior to reproduction or editing of picture data, it is desirable that readout of thumbnail picture data from the recording medium shall be completed in as short a time period as possible.
However, if the recording medium used is such a recording medium for which data is read or written at a lower read/write speed, a longer time period is required in reading out the thumbnail picture data.
As a recording method for recording thumbnail picture data on the recording medium, the following three methods have customarily been used: That is, as a first method, thumbnail data is included in a header portion of a file of a photographed still picture, referred to herein as main picture data, so that the main picture and the thumbnail are recorded as a sole file. As a second method, the thumbnail is included in a separate file from the file of the main picture and recorded continuously ahead and at back of the main picture file. As a third method, the thumbnail is included in a separate file from the file of the main picture and only the thumbnail file is stored below a dedicated directory.
However, in these three methods, the following problems have been pointed out in connection with readout of the thumbnail picture data. That is, with the first method, since it is difficult to read out selectively only the thumbnail portion from the sole file, readout time is protracted if it is tried to read out only plural thumbnail pictures, so that the data buffer area has to be increased unavoidably. With the second method, since the main file is sandwiched between thumbnail picture files, frequent accessing operations are required if it is tried to read out only plural thumbnail pictures, thus protracting readout time. With the third method, if the thumbnail picture file is stored below the dedicated directory, it is not recorded in a continuous area of the recording medium, thus raising the problem similar to that encountered with the second method.
Thus, with the conventional method, if thumbnail picture data is stored on a recording medium, such as a floppy disc, on which data is read out and written at a lower speed, the accessing time and the data buffer area are increased excessively in connection with reading out plural thumbnails.
It is therefore an object of the present invention to provide a picture recording method and apparatus whereby thumbnail picture data can be read out promptly.
It is another object of the present invention to provide a picture reproducing method and apparatus whereby thumbnail picture data can be read out promptly and a picture corresponding to one of displayed plural thumbnails can be reproduced on the display unit.
In one aspect, the present invention provides a picture recording device including recording means for recording picture data and thumbnail picture data for the picture data on a disc-shaped recording medium and control means for controlling the recording means for recording the picture data from one end of the disc-shaped recording medium and for continuously recording thumbnail picture data for the picture data from the opposite end of the disc-shaped recording medium.
With the picture recording apparatus, since control means controls recording means, the picture data and the thumbnail picture data are recorded in physically discrete areas on the disc-shaped recording medium. Moreover, the thumbnail picture data are recorded continuously from one end of the disc-shaped recording medium.
With the picture recording method according to the present invention, picture data are recorded from one end of the disc-shaped recording medium, while thumbnail picture data for the picture data are continuously recorded from the opposite end of the disc-shaped recording medium.
With the present picture recording method, the picture data and the thumbnail picture data are recorded in physically discrete areas on the disc-shaped recording medium, while thumbnail picture data are continuously recorded from one end of the disc-shaped recording medium, thus enabling prompt readout of the thumbnail picture data.
In another aspect, the present invention provides a picture reproducing apparatus including readout means for reading out picture data recorded from one end of a disc-shaped recording medium and thumbnail picture data continuously recorded from the other end of the disc-shaped recording medium, storage means for storing the thumbnail picture data or the picture data read out from the readout means, reproducing means for reproducing the thumbnail picture data or the picture data stored in the storage means, display means for displaying the picture data and the thumbnail picture data reproduced by the reproducing means, control means for controlling the readout means, storage means, reproducing means and the display means, and command input means for issuing a command to the control means. The control means controls the readout means, storage means, reproducing means and the display means for reading out all of the thumbnail picture data recorded on the disc-shaped recording medium by the readout means, storing all of the read-out thumbnail picture data in the storage means, reproducing a pre-set number of the thumbnail pictures from all of the read-out thumbnail picture data for display on the display means, reading out from the disc-shaped recording medium the picture data corresponding to the sole thumbnail designated by the command input means, reproducing the read-out data and displaying the reproduced data.
In yet another aspect, the present invention provides a picture reproducing method including reading out all of thumbnail picture data continuously recorded from one end of a disc-shaped recording medium, storing all of the read-out thumbnail picture data in storage means, reproducing a pre-set number of thumbnail pictures from all of the stored thumbnail picture data, displaying the pre-set number of thumbnail pictures on displaying means, designating one of the pre-set number of thumbnail pictures, reading out picture data corresponding to the designated thumbnail from the disc-shaped recording medium, reproducing the read-out picture data and displaying the reproduced picture data on the display means.
With the picture reproducing method and apparatus of the present invention, the thumbnail picture data associated with plural picture data present in physically contiguous areas of the disc-shaped recording medium are read out without delay and displayed, such that a picture associated with the displayed one of the plural thumbnails can be reproduced promptly.